Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Property and Equipment (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
Property and Equipment (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Jul. 01, 2018	Jun. 30, 2019	Jul. 01, 2018	Sep. 30, 2018
Property and Equipment
Property and equipment, gross	$ 165,428		$ 165,428		$ 163,364
Accumulated depreciation	(125,356)		(125,356)		(120,086)
Property and equipment, net	40,072		40,072		43,278
Depreciation expense related to property and equipment	4,200	$ 4,900	12,700	$ 15,100
Equipment, furniture and fixtures
Property and Equipment
Property and equipment, gross	131,773		131,773		131,521
Leasehold improvements
Property and Equipment
Property and equipment, gross	33,274		33,274		31,430
Land and buildings
Property and Equipment
Property and equipment, gross	$ 381		$ 381		$ 413